saving space on ipod touch - how to delete emails completely from ipod

Hello,
I have an ipod touch 2G I think....I am trying to keep as much room free on the touch as possible.
When I go to my mail account, it seems that all of my deleted mail is still on there. I can still see it even though I deleted it from the inbox. Does this mean that it is still on my ipod taking up space? How do I go about clearing my "trash" folder on my ipod touch?
thanks,
M

thanks for the response...when I drag my finger over the email, i get the option "archive" not delete.
But these emails and attached files are not saved anywhere on the ipod? There is no way to purge the "trash" folder from the ipod? I guess I could just delete and re-install the account

Check your mail settings, for your main mail account. You can auto clear messages from the server at set intervals, this is probably the issue, you need to delete them from the server, otherwise they will just sit there forever.